What is GPS?
The GPS (Global Positioning System) is a satellite-based navigation system that is made of at least 24 satellites. GPS works in any conditions of weather, anytime and anywhere you want. And it doesn’t require any subscription fees or setup charges. It was built by the US military and has been fully operational since 1995. Modern GPS receivers. Modern GPS receivers generally use a combination of both GPS and the Russian GLONASS satellites to provide improved coverage and accuracy. There are many kinds of GPS among them handheld GPS are compact and popular among the users.
How GPS works
Currently, the GPS has 31 of active satellites in orbits. The satellites orbit about 20000 km from the surface of the earth and the make two orbit a day. GPS uses so many complex technologies but, the concept of the system is very simple. Each satellite transmits a signal and orbital parameters which allow the GPS device to decode and compute the location of the satellite. GPS receivers use this information and calculate the exact location. The GPS receiver measures the distance to each satellite by the time that it takes to receive a transmitted signal. Collecting the distance measurements from a few satellites, the receiver determines a user’s position and display it to measure your running route, find a way home, map a golf course or adventure anywhere.
A GPS receiver needs to be locked on to the signal of at least three satellites to be able to calculate your 2D position (latitude and longitude) and track your movement. To show your 3D position ((latitude, longitude, and altitude) the receiver has to lock on to 4 or more satellites. Depending on the time of day and the where you are on the earth the GPS can track 8 or more satellites.
Once your position has been determined by the GPS, then it can calculate other information for you. Such as Speed, Track, Trip Distance, Bearing, Distance to the destination, Sunrise and sunset time and so on.
Overall, They work excellent and modern GPS provides extremely accurate results. So you can get a lot of help from a GPS.